22nd October
Implementing the Pratt parser: Call expressions
This one too, much to my surprise was both fun and a lot easier than I thought it would be. Consider the structure:
<expression>(<comma seperated expressions>)Turns out part of it is already done as the expression here is just an identifier
and the parser already knows how to parse those. I did guess something wrong, I thought
we'd be registering a prefix parsing func but not the case (partly). As identifiers already
have a registered prefix, that mean't only the thing that was not registered is the
comma seperated expression parsing, which requires an infix parser.
Precedence map was updated to include ( which has the highest precedence as it's a call
expression.
Off by one errors
Once the tests were completed I noticed a few of them were failing. I had read about parsers being susceptible to off by one errors, it's a whole different thing when you face them and forget about it. Luckily, it din take long to figure out that the parser was just not being updated to the right position. After I realized the first one, the other two were a lot easier to catch and fix.
Parsing is nearly complete, there a few Todo's to be removed from the code. Then I can move
on to evaluation.